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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="global.css">
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<body>
    <!--颜色，这里介绍RGB和Hex两种-->
    <div class="rgb">用RGB表示颜色</div>
    <div class="hex">用Hex表示颜色</div>

    <!--颜色可以赋给任何需要以颜色为值的语句-->
    <div class="background-color text-opacity">背景颜色</div>
    <div class="border-color opacity">opacity边款颜色</div>
</body>
</html>